Wireless terminal position detecting device and method

• US 7,230,577 B2
• Filed: 08/16/2004
• Issued: 06/12/2007
• Est. Priority Date: 09/01/2003
• Status: Expired due to Fees

• Current Assignee: Omron Automotive Electronics Company Limited (Nidec Corporation)
• Original Assignee: Omron Corporation
• Inventors: Tanaka, Akitomo
• Primary Examiner(s): CHEN, SHIH CHAO
• Application Number:
  US10/919,882
• Publication Number:
  US 20050046568A1
• Time in Patent Office: 1,030 Days
• Field of Search: 340/5.61, 340/425.5, 307/10.1, 343/711, 343/713
• US Class Current: 343/711
• CPC Class Codes: B60R 25/245 where the antenna reception area plays a role
• CPC Class Codes: G01S 3/20 derived by sampling signal received by an antenna system having periodically-varied orientation of directivity characteristic
• CPC Class Codes: G07C 2209/63 Comprising locating means for detecting the position of the data carrier, i.e. within the vehicle or within a certain distance from the vehicle
• CPC Class Codes: G07C 9/00309 operated with bidirectional data transmission between data carrier and locks
• CPC Class Codes: H04B 7/0604 with predefined switching scheme

Abstract

A wireless terminal position detecting device for a portable device includes a plural n-number of transmission antennas disposed such that a portion of their reachable areas overlap, a signal dividing device for dividing a request signal into the plural n-number of divided parts, and a signal distributing device for causing the divided parts of the request signal to be transmitted sequentially from these transmission antennas. The position of the portable device is detected based on an answer signal returned from the portable device in response to the request signal.

Claims

1. A wireless terminal position detecting device comprising:

a portable device;

a plural n-number of transmission antennas each having a reachable area inside which communication is possible, said transmission antennas being disposed such that a portion of the reachable areas of said transmission antennas overlap;

a signal dividing device for dividing a request signal into said plural n-number of divided parts; and

a signal distributing device for causing said divided parts to be transmitted sequentially each from different one of said transmission antennas;

wherein said portable device serves to synthesize said divided parts of said request signal to thereby receive a synthesized request signal as the request signal before the division and to return an answer signal in response to said synthesized request signal; and

wherein the position of said portable device is detected based on said answer signal returned from said portable device in response to said request signal.

2. The wireless terminal position detecting device of claim 1 wherein said signal dividing device divides said request signal into said divided parts such that said divided parts have mutually overlapping parts.

3. A wireless method of detecting the position of a portable device, said method comprising the steps of:

positioning a plural n-number of transmission antennas each having a reachable area inside which communication is possible, said transmission antennas being disposed such that a portion of the reachable areas of said transmission antennas overlap;

dividing a request signal into said plural n-number of divided parts; and

causing said divided parts to be transmitted sequentially each from different one of said transmission antennas; and

causing said portable device to synthesize said divided parts of said request signal to thereby receive a synthesized request signal as the request signal before the division and to return an answer signal in response to said synthesized request signal;

wherein the position of said portable device is detected based on said answer signal returned from said portable device in response to said request signal.

4. The wireless method of claim 3 wherein said request signal is divided into said divided parts such that said divided parts have mutually overlapping parts.

5. A wireless terminal position detecting device comprising:

a portable device;

a plural n-number of transmission antennas each having a reachable area inside which communication is possible, said transmission antennas being disposed such that a portion of the reachable areas of said transmission antennas overlap;

a signal dividing device for dividing a request signal into said plural n-number of divided parts;

a signal distributing device for causing said divided parts to be transmitted sequentially each from different one of said transmission antennas; and

a control unit for detecting the position of said portable device based on an answer signal returned from said portable device in response to said request signal;

wherein said portable device serves to synthesize said divided parts of said request signal to thereby receive a synthesized request signal as the request signal before the division and to return said answer signal in response to said synthesized request signal.